The overall objective of this proposal is to design a high quality Nutrition Coordinating Center (NCC) which would serve the MDRD Study and support the major aim of that study to test hypothesis that nutritional variables, specifically dietary protein and phosphorus, and related to the progression of chronic renal disease. In order to fulfill this objective the NCC will work collaboratively with the MDRD clinical centers, the Data Coordinating Center, other central units, and the staffs of the National Institute of Diabetes and Digestive and Kidney Diseases as well as the Health Care Financing Administration. The primary responsibilities of the proposed NCC will be: 1) Design the protocol for nutrition assessment, intervention, and follow-up. 2) Design and/or selection and refinement of measures for estimating compliance in individual participants as well as the randomized study groups. 3) Develop the appropriate materials for assessment, intervention, follow-up, compliance monitoring, training, certification, and intervention evaluation. 4) Design and implement appropriate training for clinical center personnel involved with nutrition assessment procedures, and nutrition intervention and follow-up activities. 5) Analyze dietary data and design analyses to provide maximum feedback to clinical centers on compliance patterns within randomized groups. 6) Assist in the development of procedures for monitoring nutritional adequacy.